Range Report Cold bore shot

[jdg300rum]

I want to pick some brains for a min. I have a rifle that shoots about a min high at 1000 yards and the shots that follow are with my regular dope. I have chrono the load and is very good sd around 9 or 10. I do know the first shot is faster than the rest time after time. I am using retumbo 97 grains in a 338 lapua improved 40. This usually the rule concering the cold bore shot. I have tested this several times. The load shoots around 1/2 moa at the distance if you do not count the cold bore. Any ideas?

 

[Topstrap]

Re: Cold bore shot

Hold 1/2moa low on the first shot? If it's consistent every time and can't find anything obvious causing it then that is an easy solution.

I'll ask before anyone else though, is this with a clean barrel? If so foul it first before the first shot that counts. Another idea may be the shooter, being the first shot are they sure they are doing the same thing with each round fired after the first one? Might also be the bags or setup not being the same and settling in. With that small of a variation it's something really small if you can keep it consistent at 1/2moa after that.

Great shooting

Topstrap

 

[Niles Coyote]

Re: Cold bore shot

Cold shooter maybe, helped this guy out...

http://www.snipershide.com/forum/ubbthre...rue#Post3434649

 

[jdg300rum]

Re: Cold bore shot

I have logged a few shots and its usually about the same. The rifle is not clean when I am shooting cold bore. I always foul the barrel first. I am going to try again today and see if it repeats. I think I am doing my part at that range. I color coat my bullets with a sharpie different colors. Yesterday for instance I shot six shots. The first was a min higher than my dope and the other five printed a 3.75 inch group. I am wondering if it could be the way the retumbo burns in the barrel? Maybe slowing the velocity?